The invention relates to a miniature linear motion actuator and a driving mode thereof, and belongs to the technical field of linear motion actuators. The linear motion actuator comprises end caps, an inner iron core, outer magnetic yokes, a coil, a coil bracket and two steel magnets, wherein identical poles of both steel magnets are oppositely arranged on both ends of the inner iron core, while the outer ends of both steel magnets are respectively provided with the end caps inside both end caps, the peripheries of the inner iron core and the steel magnets are provided with two symmetrical cambered magnetic yokes both cambered magnetic yokes are approximately formed into a circular ring on the periphery of the inner iron core a slideway is formed between both cambered magnetic yokes air gaps are formed between the magnetic yokes and the inner iron core and between the magnetic yokes and the steel magnets the coil is arranged between the inner iron core and the magnetic yokes and is fixed with the coil bracket both ends of the coil bracket extends out of the magnetic yokes through the slideway and the coil and the coil bracket can slide on the slideway between the magnetic yokes. The miniature linear motion actuator has the advantages that identical poles of both steel magnets are arranged oppositely, which ensures better magnetic circuit sealability and evener magnetic filed formed between the air gaps moreover, the miniature linear motion actuator has simple structure and is suitable to be used as the actuator of a miniature mechanism.